Vehicle driving systems have conventionally been known which include a motor and a power transmission device for changing a power transmission capacity of a power transmission path between the motor and wheels. For example, in a vehicle driving system described in Patent Literature 1, it is described that the application force of a hydraulic brake is controlled according to the viscosity of oil in consideration of the fact that an application force that is required on a hydraulic brake as a power transmission device changes according to the viscosity of oil used.
It is also described that in regeneration, a vehicle is slowed through regenerative braking by applying strongly the hydraulic brake and driving a motor for regeneration and that kinetic energy obtained is converted to electrical energy to charge the battery.